In a continuous production line wherein a substance in liquid, semi-liquid or pasty form may be filled into containers it is desirable to monitor the quantity of the substance filled into each container. Prior art checkweighers have often been placed in or under a conveyor transferring the filled product from a filling station to a station for subsequent processing, such as packaging.
Weighing the products while on an intermittently or continuously moving conveyor may appear to be efficient and cost effective. However, such an arrangement may often result in inaccurate readings, especially if the product is moving or if it is not stopped in the exact position required for weighing. Also, if an interruption occurs in the production the synchronization of the position of a stopped product relative to a checkweigher may not coincide with the desired position for weighing. An additional problem is that adjacent products may not be correctly spaced, resulting in inaccurate weight readings for consecutive products.
An object of the invention is to overcome the above problems by providing an improved method and an apparatus for weighing individual products which allow products to be placed in the correct position on a checkweigher every time, and which allow products to be weighed with an improved accuracy.